class cat:
    def __init__(self, luntai="轮胎", yanse="白色", chuanghu="褐色", xinghao="大众"):
        self.luntai = luntai
        self.yanse = yanse
        self.chuanghu = chuanghu
        self.xinghao = xinghao

    def guadang(self, a="前进"):
        self.jiayou()
        if a == "前进":
            self.qianjin()
        elif a == "后退":
            self.houtui()
        elif a == "刹车":
            self.shache()
        else:
            print("档不对")

    def qianjin(self):
        print("%s在前进" % self.xinghao)

    def houtui(self):
        print("%s在后退" % self.xinghao)

    def wurenjiashi(self):
        print("%s在无人驾驶")

    def shache(self):
        print("%s在刹车")

    def jiayou(self):
        print("加油")


c = cat()
# c.qianjin()
# c.houtui()
c.guadang()

c1 = cat(xinghao="奔驰")
c1.qianjin()